1. Field of the Invention
The present invention relates to a wireless communication apparatus and communication method thereof, and more particularly to a wireless communication apparatus, a method thereof and a wireless communication system capable of transmitting and receiving data via a plurality of channels in a Bluetooth system. The present application is based on Korean Patent Application No. 2001-5289, which is incorporated herein by reference.
2. Description of the Related Art
Bluetooth communication has become popular recently, because it enables transmission of data such as audio data, video data, etc at a maximum speed of 1 Mbps within a distance ranging from 10 m to 100 m.
The general Bluetooth system uses an Industrial Scientific Medical bandwidth of 2.4 GHz. FIG. 1 shows the structure of a piconet in the general Bluetooth communication system.
Referring to FIG. 1, the Bluetooth communication system includes one master device M and a plurality of slave devices S1-S7 connected with each other. As described, the network in which one master device M is connected with at least one slave device S1-S7, is called a ‘piconet’. In one piconet, a maximum of seven (7) slave devices can be connected to one master M.
FIG. 2A shows a frequency channel of the general Bluetooth communication system.
A pair of devices, i.e., one master device and one slave device, communicates with each other through one of seventy-nine (79) channels of 1 MHz bandwidth in the frequency band of 2.4 GHz for a time corresponding to a certain number of time slots (625 μs-3.125 ms). Data transmission rate per channel is 1 Mbps.
Further, in order to prevent interference among channels and fading effect during communication, a Frequency Hopping method is employed.
FIG. 2B shows the frequency hopping among the frequency channels of FIG. 2A.
The data is exchanged in packets through the channels, and the respective packets are transmitted in another hopping frequency. One packet is comprised of one, three, or five time slots.
In the current Bluetooth system, however, since the master device and the slave devices communicate in series only through one channel, there is a limit on the transmission speed.
Accordingly, even when there is much data to send, the data has to be transmitted at a limited speed.